I share custody of my 2 year old daughter. Her father has a 5 year old from a previous relationship. We are on good terms and spend time with the girls together when possible. The issue is the 5 year old's mother does not discipline her or have any expectations of her. She lacks manners and everything goes smooth as long as she gets her way. When she doesn't everyone in the house has to suffer for it. Her father also struggles with disciplining her effectively and is not consistent. The 5 year old also bullies my 2 year old which I don't stress too much about because I do believe they need to learn to work out their own issues to an extent. My question is how do I undo and protect my daughter from the terrible influence that her half sister is? I worry that it will be too much for me to overcome as her mother.